Folding square.



FRANK G. VWAGNER, 0F LOS ANGELES, CALIFORNIA.

d VFOLDING SQUARE.

Specification of Letters Patent.

Patented Nev. e, 19.17.

Application led August 15, 1916. Serial No. 115,017.

To all whom t may concern.'

Be it known that I, FRANK G. WAGNER, a citizen of the United States, residing at Los Angeles, California, have invented a certain new and useful Improvement in Folding Squares, of which the following is a specification. l

My invention relates to squares, and consists of the novel features herein shown, de-

scribed and claimed. Y

Figure 1 is a plan view of a folding square embodying the principles of my invention, with the parts in their normal square positions.

Fig. 2-is a fragmentary view analogous to 'Fig'. 1 with the parts folded to make an yangle of V45 degrees.

Fig. 3 is an enlarged cross-sectional detail on the line 3-3 of Fig. 2. f Fig. 4 is an enlarged edge view looking in A'the' directionindicated by the arrows'4 in iigs. 2 and 5, and showing the parts latched in square position.

Fig. 5 is a fragmentary plan section on a plane parallel with Figs. 1 and 2 and yon the line 5 5 of Fig. 4 and looking in the direction of the arrows.

the line 3make a standard framing. square, and the object of 'my invention isto Join'V said legs so that they may be folded to' 'parl allel positions or set at any angle between parallel and 90 degrees or right angle.

The point 4, the inner end of the line 3, is the center upon which the secondary leg 2 swings relative to the primary leg 1, said point 4 being the inner corner of the secondary leg 2 at the abutting end. A slideway 5 is formed from the side face of the primary leg 1 concentric to the point 4, thus leaving a half-round pivot 6, said slideway 5 describing a semi-circle in plan terminating at the side edge of the primary leg 1, and said slideway being rectangular in crosssection. A recess 7 is formed from the same side of the secondary leg 2 to match the slideway 5. The legs may be placed together -edgewise as in their folded positions or as in their square positions and then the slideway 5 and the recess 7 may be turned or milled at the same time with the same tool, thus insuring a match. The tongue 8 is exactly three-quarters of a circle in plan and rectangular in cross-section and fits tightly in the recess 7 and is rigidly secured therein by brazing, soldering or riveting or the like, and said tongue lits slidably in the slideway 5, so as to form a hinged connection between the legs l and 2, the centerof the hingebeing the point 4. Forming the recess 7 leaves the quarter-round supporting stud 9, matching the half-round pivot 6, and the central k'opening 10 in the'tongue 8 is small enough to fit tight around the pivot 6 and the stud 9 so that the corner of the secondary leg 2 -wlll press tightly against the edge of the primary leg 1 at the point 4, at all times so as to prevent yielding or shaking of one leg relative to the other and so as to make a good friction joint. Y' y A The screw-threaded* clamping Astud 11 is xed through the metal of the primary leg 1 and projects'through the slideway 5 at its cross-sectional center and at a point at an angle of--45 degrees-toward 'the head end e of the leg 1 from the point 4. A slot 12 is `formed through the extending part of the tongue 8, said slot being concentric in plan and the stud 11 being at the cross-,sectional center of the slot, and said yslotV being stepped incross-section to form the retaining Vflanges 13 and 14 extending toward the stud 11 at the bottom V ofthe slot-12 and against the metal at the bottom of the slideway 5. A kidney shaped washer 15 is stepped all the way around to lit slidingly in the slot 12 and to lit the flanges 13 and 14 and to extend between said ianges and jam against the metal at the bottom of the slideway and said washer has a central opening fitting the stud 11 and a recess in its upper or outer face to receive the nut 16 upon the stud 11, said nut being slotted to receive a spanner key for operating the nut.

The parts are accurately made so that when the nut is tightened the washer jams against the metal around the stud and makes a good friction fit to allow the tongue to slide in the slideway without shaking. The legs may be readily separated by removing the nut. When finishedA the faces are all substantially flush.

The parts thus constructed and assembled make a complete folding square with a friction joint. If the nut is thinned so that it will not jam against the bottom then the parts may be clamped in any adjusted position by tightening the nut.

In order to hold the parts rigid and eXact in their square positions and not depend upon the friction joint I provide a latchbar 19 and form a stop 20 and a spring seat Vover the pin to normal position.

21. The expansive coil spring 22 is placed in the spring `seat 21, the latch bar 19 is placed in the chamber against the stop v2() with its outer face flush With 4the outer face of the leg and said latch bar is secured in place by the pivot pin 23, and said latch bar 19 has a vhook 24 extending-beyond the end face of the secondary leg. A hook chamber 25 is formed from the end face of the head ofthe primary leg 1 and a latch pin 26 is fixed in position toextend through the hook chamber and bel engaged by the hook 21, said hook being beveled yto snap In end elevation as in Fig. 1 the latch ts the chamber except that there are two recesses 'one upon either side of the latch 27 to receive the end of the operators finger for pressing inwardly to release the latch.

An indicator mark 28 is formed upon the primary leg 1 intransverse alinenient with ,y

the. point-and the space upon thetongue 8 yvhlch passes this indicator has the vgraduations 29 reading from 0 to 90, being a quarter of a circle, so that the square may be A K y l y tending from its end and matching the slide- Way; a tongue fixed iny therecess andSlidused as a protractor. The remaining quadrant of the extending tongue 8 has the roof pitch scale graduations 30 reading 1 6, 1 1, 1 3, 1 2, 2 3,3 f1.

I claim: v

1. In a folding square, a primary leg having a slideivay semi-circular in plan extending from the inner edge of its head and leaving a semi-circular pivot; a screwthreaaedtud extending through" said Slide- Way; a secondary leg having a recess extending from its end andy matching the slidevvay;

ya tongue xed in the recess and slidingly7 'ixed'in the slideWay and having a slot for nut on the n tending from its end and matching the slidevWay and leaving a quarter-round lstud vfitting the half-round pivot; a tongue fixed in the recessand slidingly fixed in the slide- Way and holding rthe Ycorner rof said quarterround stud tightly against kthe fiat side of the half-round pivot andhaving a yslot for the screw-threaded stud;V and a nut upon thestud and a Washer upon said study and beneath said nut. i l Y 3. In a folding square, a primary leg havand leaving a semi-circulanpivot;A a screwthreaded stud extending. through saidslideway; a secondary leg having arecess exingly fixed in the` slid'eway and"having a vstepped slot for said stud; a Washerin said stepped slot/'around said stud; and a nut upon the stud and recessed into the Washer.

In testimony whereof I aiiix my signa- Copies of this patent may be obtained for vve cents each1 'byvaddrsisiwng the Commissionerlof latent's,

i Washington, I). C.

mg a slideyvayk semi-circular in planV ex- 

